Add support for query results and instantiation

Author: markusjwetzel

src/Inheritance.php

@@ -3,6 +3,7 @@
 namespace ProAI\Inheritance;
 
 use Illuminate\Support\Str;
+use Exception;
 
 trait Inheritance
 {
@@ -20,14 +21,35 @@ trait Inheritance
      */
     public static $inheritanceType;
 
+    /**
+     * Create a new Eloquent model instance.
+     *
+     * @param  array  $attributes
+     * @return void
+     */
+    public function __construct(array $attributes = [])
+    {
+        $type = $attributes[static::$inheritanceColumn] ?? null;
+
+        if (static::isRootModel() && $type) {
+            [$one, $caller] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 2);
+
+            if (! isset($caller['class']) || ! $caller['class'] || ! $this instanceof $caller['class']) {
+                throw new Exception('Model cannot be instantiated. Please use '.static::class.'::new instead.');
+            }
+        }
+
+        parent::__construct($attributes);
+    }
+
     /**
      * Bootstrap the inheritance trait.
      *
      * @return void
      */
     protected static function bootInheritance()
     {
-        if (! static::modelInherited()) {
+        if (static::isRootModel()) {
             return;
         }
 
@@ -41,13 +63,13 @@ protected static function bootInheritance()
     }
 
     /**
-     * Check if model is inherited.
+     * Check if model is root model.
      *
      * @return bool
      */
-    protected static function modelInherited()
+    protected static function isRootModel()
     {
-        return self::class !== static::class;
+        return self::class === static::class;
     }
 
     /**
@@ -61,7 +83,88 @@ protected static function getInheritanceType()
             return static::$inheritanceType;
         }
 
-        return static::$inheritanceType = static::class;
+        $class = static::class;
+        $flippedMap = array_flip(static::$inheritanceMap ?? []);
+
+        if (isset($flippedMap[$class])) {
+            $type = $flippedMap[$class];
+        } else {
+            $type = $class;
+        }
+
+        return static::$inheritanceType = $type;
+    }
+
+    /**
+     * Create a new instance of the model by type.
+     *
+     * @param  array  $attributes
+     * @return static
+     */
+    public static function new($attributes = [])
+    {
+        $class = static::getChildClass($attributes);
+
+        if ($class) {
+            return new $class($attributes);
+        }
+
+        return new static($attributes);
+    }
+
+    /**
+     * Create a new instance of the model by type.
+     *
+     * @param  array  $attributes
+     * @param  bool  $exists
+     * @return static
+     */
+    public function newInstance($attributes = [], $exists = false)
+    {
+        $class = static::getChildClass($attributes);
+
+        // This method just provides a convenient way for us to generate fresh model
+        // instances of this current model. It is particularly useful during the
+        // hydration of new objects via the Eloquent query builder instances.
+        $model = $class ? new $class : new static;
+
+        $model->exists = $exists;
+
+        $model->setConnection(
+            $this->getConnectionName()
+        );
+
+        $model->setTable($this->getTable());
+
+        $model->mergeCasts($this->casts);
+
+        $model->fill((array) $attributes);
+
+        return $model;
+    }
+
+    /**
+     * Create a new model instance that is existing.
+     *
+     * @param  array  $attributes
+     * @param  string|null  $connection
+     * @return static
+     */
+    public function newFromBuilder($attributes = [], $connection = null)
+    {
+        $attributes = (array) $attributes;
+
+        $type = $attributes[static::$inheritanceColumn] ?? null;
+
+        $model = $this->newInstance([static::$inheritanceColumn => $type], true);
+
+        $model->setRawAttributes($attributes, true);
+
+        $model->setConnection($connection ?: $this->getConnectionName());
+
+        $model->fireModelEvent('retrieved', false);
+
+        return $model;
     }
 
     /**
@@ -93,4 +196,29 @@ protected function getRootClass()
     {
         return self::class;
     }
+
+    /**
+     * Get the class name of the child class.
+     *
+     * @param  array  $attributes
+     * @return ?string
+     */
+    protected static function getChildClass($attributes)
+    {
+        if (! static::isRootModel()) {
+            return null;
+        }
+
+        if (! isset($attributes[static::$inheritanceColumn])) {
+            return null;
+        }
+
+        $type = $attributes[static::$inheritanceColumn];
+
+        if (! isset(static::$inheritanceMap)) {
+            return $type;
+        }
+
+        return static::$inheritanceMap[$type] ?? $type;
+    }
 }